Internal-combustion engine



. w 1,62 84 Apr1l5,1927. a R. BURNETT INTERNAL COMBUSTION ENGINE Filed May 31. 1923 1& A 2

Patented Apr. 5, 1927.

EVERETT R. BURTNETT, OF LOS ANGELES,

CALIFORNIA, AssreNon, nrnrnnor AND MESNE ASSIGNMENTS, Toi'rnn A'oroMorrvn VALVES 00:, or. Los ANGELES, CALI- FGBNIA, A. VOLUNTARY rrnusn lNTEBNAL-CQMBUSTION Enenvn Application filed May 31,

My invention relates generally to internal combustion engines, and more particularly to anengine of the four stroke cycle type, the principal object being to generally improve upon and simplify the construction of the existing forms of four stroke cycle'internal for mechanically inducting into the combustion chamber, a two part charge, one part being an inert volume non-throttled and con-- stant in volume during the period of the first 'part of the piston induction stroke and the second part being a volume of gaseous fuel mixture that is throttled and variable in volume during the last part or" the period of-the pistons induction stroke, and during which. induction of the gaseous mixture, the inertvolume supply has been cut on".

A further object of myinvention is to provide a. four-stroke cycle internal combustion engine structure and method of operat on wherein a relatively high degree of compression can be used without detonation and I in which engine long periods of full load operation will not cause distortion of the-engine parts as a result of excessive heat'and in which engine the ratio of gaseous expansion is materially increased with respect to a given quantity ofvfuela A further object of the invention is to provide a four-stroke cycle internal combustion engine in which a two part charge is inducted mechanically and successively, said engine having acombustion chamber of the least possible Wall area compatible Wltlltlifi design most practical for silent and continued operation and with minimum cost of manufacture. l Further objectso't my invention are to provide in an engine of the character referred to a valve arrangement that may be easily and cheaply produced, and which will.

1923. Serial No. 642,508.

, inert first part charge; and, further, to provide for the st-rati-fication and confinement of the gaseous mixture within the valve, pocketwhere it maybe instantly ignited and complete combustion effected.

Further objects of my invention are to provide an internal combustion engine in which instant or auto-ignition from charge temperatures, or from compressions pressures, will not cause detonation, such. result being attained by reason of the presence of a constant, stratifying, inert volume that holds in check the pressure rise. from the ini tial stage of combustion and absorbs heat as an inert volume from the gaseous volume, the combustion of which generates heat; to

provide in an internal combustion engine for g the absorption of the shock resulting from the instantaneous combustion of" the gaseous fuel charge; and to provide for the absorption. of pressure variations; to provide 'for the centering of the fluctuations and producing uniform expansion, and which actions be compared to a flywheel. which; inits duty absorbs the sharp. impulses of power and gives back smooth twisting effort. A still. further object of my invention is to provide internalcombustion engine in which a constant inert volume of free cool air. i Y

or cooled products of combustion, is inducted into the cylinder first and for the period during the piston movement through the first half of the stroke, thereby providing anatmospheric pressure condition Within the cylinder at the time of the-cutting off of the in ert volume supply and the beginning-of the induction of the throttle cont-rolled volume of gaseous fuel nurture, and which-action produces within the cylinder at the time of v the admission of the gaseous fuel mixture a non-rarefication condition of the inert v01- ume,..and consequently efiecting stratification of the two part inducted charge.

. A still further object of the iaveaaoa isito provide in an engine of-th'e character described a spec al form or combustion chamber with particularly arranged valve means and; novel cam andwvalve actuating meclr anism Wherebya successful two part chargeinduction and charge stratification is accomplished.

Viththe "foregoing and other objects in view, my invention consists in certai'nnov'el" 'featuresott construction and arrangements of that will bemore fully hereinafter described, and illustrated in the accom'pa 'iying drajyvings, in which,

F'g. 1 is a vertical section-"takenlength wise through the centerofan internal cola busti'on engine of m improved Construction. i

scale, and taken approximately on'the line Fig! 3 isa vertical section taken on line 3 3 of Fig;:1.,

Referring by. numerals to the ac om anying drawings, designates a shell or houlsing that serves the upper part or the crank case ofthe engine inasmuch as it is positionedion top off the lower part 11 of the crank case,-and formed integral the'u'pper portion of said j shell or housn'i'g isa 'cylindei 12, or, a series of cylinders,

where the engi'n e' is a multi-cylinder type.

Formedin the end w'a'llsof partslt) and are bearings for a cr'ank shaft 13 hav ing' a crank 14 on which is j ournaled the lower end of a connecting rod 15, and the up er end of the latter. being connected, to the wristpin ot'a piston 16 that is arranged 1 for reciprocatorymovement in cylinder 12.

Formed integra-lwith the upper portion 'o'fatheshell or casing 1-) and to the side of; the cylinder 12 is a block 17, through which is formed an inert volume duct or passageway 18 and a gaseous fuelinlet duct -19.' The inner end of duct 18 terminates adjacent to the clearance or chamber within cylinder 12,;and formed} at the inner; end of said duct is a seat-tor an ordinary poppet valve 20 having'a depending stem 21. I

The inner end of tliefuel inlet d-uct'19 terminatesadjacent to and outside of one end fotduct 1 8, andtormed at theinne-r end of said duct 19 is; a seat for an erdinarypoppet valve 22having a depending stem 23; Thus, the arr and gas lnletvalves 20 and 22 ja1'e directlyjin line Vltl1':ea(il1 other and with the axis of cylinder 12 and with the air inlet valve 20 disposed betweengas inlet valve 22 and the piston-clearance chamber within cylinder 12. i

Fig. 2 1s a horizontalsection on a reduced Secured on top of the housing 10 is a head plate or block 24L in the underside of which is formed a 'shallow'recess 25 that communicates directly with the inner ends of the ducts 18 and l9 and with the piston cle rance chamber in cylin'de'r' 1 2 Thus, the recess 25 provides a du'ctwhich permits the inert'volume and the gaseous fuel volume a to enter the piston clearance chamber, and

said recess alsotperi ormsthe functions or a charge compression, conibu'stron andelxpansion chamber.

Leading from point in chamber 25,

preferably directly above the inner. end 10f duct 18 is anexh'aust duct or passageway 26, the inner end thereof being, provided wi 1 a seat for ano rdinary poppet Valve 2'? having an upwardlyprojectingstem 28, said stem operating through a suitable bearing 29 and having associated with it :a

- spring 30" which acts to normally retain the valve uponits seat.

Seated" in the headf2l preferably a point above the innjer end of gaseous i' uel duct l9 is, an" ignition device, preferably, a spark plug'31 and the, terminals of the electrodes thereof project into thechamber 25 directly above the gaseous fuel inlet 22.

The valve stems 21;. and 23 are, arranged for sliding movement through suitable bearings 32 and 33,-respectively, and associated with the lower-portions of said stems are respectively springs 34: and 35 that act to normally hold the valves 20 and '22 upon their seats, I I i v n Arranged for rotation in suitable bearings above and to one side of thecrank shaft 13 vis a cam shaft 36 having a' cam 37 that isadapted to actuate suitable mechanismto unseat the valves 20 and 22, and formed on said cam shaft adjacent to the cam 37 isa second cam 38 that is adapted to actuate certain mechanism to unseat the exhaust valve 27. The camshaft 36 is arranged to rotate at halfspeed on the crank shaft 13, preferably by means of suitable gearing between-said shafts.

ably located bracket 43. The opposite end of this rocker arm 4:2'carries anad-justable memberdathat bears on the upper end. of the exhaust valve Sten1'28.

Journalled on a-p'inz lea that projects laterally from bracket 39 is a rocker arm 46 ill) bearing against theunderside of one en'dot arocker arm 42that1s ournztled on a suitcrank shaped rocker arm 52 that is practically a duplicate of rocker arm 45, and

journalled in the bifurcated longer arm of said rocker arm 52 is a roller 54 that rides on the periphery of cam 37.

The short arm of the rocker 52 carries an adjustable member 53 upon which bears the lower end of valve stem 21;v

With the parts of my engine positioned as illustrated in Fig. 1, piston 16 is at the upper end of its travel following its exhaust or scavenging stroke. 'As piston 16 starts downward on the charge induction stroke, the lobe of cam 37 bears against roller 54, thereby rocking member 52 so as to lift valve stem 21 and unseat the inert volume inlet valve 20, and, dueto the length of the lobe of the cam 37, said valve is maintained open for approximately half the downward stroke of said piston 16. Thus, during the first portion of the induction stroke of the piston, an inert volume of cool air, or cooled products of combustion, will be drawn through duct 18 and chamber 25 tolill the piston clearance space directly above the head of the downwardly moving piston. I {As the lobe of cam: 37 passesroller 54,

' spring 34 will act to close valve 20, and imeons fuel inlet valve 22 from its seat.

mediately thereafter the lobe of cam 37 engages roller 48 to rock member 46, thereby moving stem 23 upward and lifting the gas- This action takes place, and the valve 22 is held open during the latter half of the downward travel of piston 16 on the induction stroke, and while said valve 22 is held open a charge of gaseous fuel in inducted into the upperportion of the clearance chamber within cyl- -inder 12, and which gaseous fuel charge overlies the preceding inert volume that was drawn into the cylinder. I

As the lobe of cam 37 passes roller 48, spring 35 returns valve 22 to its seat, and upon the succeeding upward or compression stroke, the piston 16, the inert volume and the charge of gaseous fuel will becompressed in stratified relation within chamber 25 with the compressed gaseous fuel occupy ing that end of the chamber that is occupied by valve 22 and theinner end of the spark plug 81, and with the compressed inert volume occupying that portion of the chamber that is practically above piston 16. g It will be understood that the compression stroke of the piston 16 will produce a certain amount of turbulence in chamber25, but the greatest degree of such turbulence takes place in the intermediate portion of said chamber or in the spacebetween valves 20 and 27.

Owing to'the narrowness of that portion of chamber 25 between valve 22 and spark plug 31, the turbulent action occurring in the intermediate portion of said chamber 25 gradually decreases toward the narrow"por tion of saidchamber between valve22 and spark plug 81, so that, at thepoint of highest compression thereis a small volume of practically undiluted gaseous fuel in the chamber into which the spark plugprojects. Further, the degree of turbulence produced within chamber 25 is not sufficient to entirely swee away the stratum of inert volume-that hes directly against the head of piston 16, during its compression stroke. In

this connection, it has been demonstrated 7 in repeated tests and experiments that in the turbulence chambers of internal combustion engines there is always a thin stratum or skin of gas or air that lies against the surfaces of the walls of saidchamber and which stratum is practically undisturbed during turbulence of the gaseous fuel charge that is under compression.

At the point of highest compression, or,

when piston 16 passes highcenter, or immediately thereafter, the compressed gas eous fuel charge is ignited by a'spark pro- 3 ducedbetween the "terminalsfof the felectrodes of plug 31, and the resulting explosionacting through the highly compressed stratum of inert volume forces the piston 16 downwardon its power stroke. Owing to the presence of the inert volume between the head of the piston and the compressed charge of gaseous fuel, the relatively high temperatures resulting from combustion of the fuel will not be transmitted to the piston, and the wall of the cylinder 12, and as the spark that ignites the compressed fuel charge is produced practically in the center of the compressed charge, there will beno detonation such as would ordinarily result where the spark is produced at one end or side of the compressed fuel charge. s

As the piston reachesthe lower end of its power stroke the lobe of cam'38 bears against. the lower end of plunger 40, thereby lifting the same and its associated push rod 41, and as a result, rocker 42 ls'swung upon its axis to move'valve stem 28 downward, thereby unseating exhaust valve 27, and as the latter is maintained in open or unseated position during the succeeding upward stroke of pisten 16, the products of combustion and burnt 1 gases will be forced from chamber 25 past 27 and out through the open exhaust valve duct 26. v p I An internal combustion engine of my improved construction is'comparatively simple,

a maybeeast tchea -1y yadtaee aii es Y charge cosifstirig of @111 inei ft olnfne and likextis'e. disposed so, as to p'fevent the time:

mission of high ,t'empefmies ffoin the nae a ehal getc the bis'tofrf my the snfronncl I t I t v H j y I coniloustio'n clearance chamber extending It in be eets-woe that miller anges in the constrtesomaoem Otis-zei? theme:

in-ishownand described Without de'fiatting hem th spirit ofthe" invention, the scope I claimas my menses:

1; In 0111 str kecycle mesh ttstisn--engine, a bro-ck e evated with" a contusion chamber and a pan" of n lfet nat'e aeth'e topj' sin fa ce of gal-e515 I v behind the other and both in line with the v .a'z iis of the confblistion chamber"; a head-for said block, which head is provided s its uiid'f sifc'lewi'th a shallow recess that pro;

Vides fa cleafance fer the: tlon chamber, saldd ecess havmg enemasion that oveflies the inner; ends of the inlet 'du'cts', an exliai'i st leading" tp weary from the causal p Valve normally closing'th' 'inne 'f end otsai'd exhaust duct,

J downweedi valves .u '1.

n'ormally fclos gthe inter-ends of duets; a piston afrahged; for epe auoa positivelj lf unsating; se hence, the sli'ction 'stf'okeof the piston, the" inlet duct contiolli ng valves arid means for posimilfln; A 2 5i z A tively unseating the exhaust duct control v during the" exhaust stroke of said piston. I t V Y 25111 a; fem-"stroke cy'cle interfial con] hus'ti'on engine, a block p'r'oi'fid'ed with a -i.n1etducfts,'theend of wh ch dates tj'er'mt hate; at the top surface fsa'id block, one behind the other and both in linewith the axis of the combi lstion chamheff, for said block, wli'lchfhe'ad is prov ded in ms undef' side with a shallow recess that protionchamhen' said recess having an exten sion that (Wei-hes the inner" ends of the finlet ducts", exhaust dlfct leading up-- -Wa'1"'d1y fft'nn the central Y ooftion of said clearancechatter;-a do'WnW'afdly opening valve no 1 exliafistchict, downwardly seatingv alves during the slictlon s tiokeofth iston, the

I inletthrct 'col'ltl'ol'ling" Valves, means for toh and ignition means seatedin' said head and plf ojec'ting into the exte nsion of' the clearance chanibe'i' at point above the outer one of the 'do'wnwaidly seating valt' es'. v 3. In a fonf'strolze cycle intefn'ail comblif'stion eh "me, a combustion cylinder, a

laterally from the'head end of the co mhus tion chamber, three valves seated in the Wall of said common clearanc-echaln'hei, each of said three Valves controlling a .sepafate i u n; mi 1 duct that communlcates With said common cle'aiance chamber, the axis of said three valves being arl 'a'nged in -direct alignment with each other and with the aLXis of the coinbnst'ioii cylinder and disposed at right.

an les w the 'cfa'nli' sh'aitt of the engine and bhfstion en lie, :11 comjlou'stion cylinder, a I for ope'ration therein, crank shaft to which said fii'ston is" con'-. nected; af common con'ipfession an'clcomhhsrun, nston 'aTran ed tion I cleai an'ce chamber eitending laterally from the head end of the conihustion char loci, a" pan" of separate charge i'lolume inlet duets laling bathe lot v''r ortion of said common "clearance chamber, theinner ends 'oifsai d'dhcts beingdisposed'oflebehind the. othef and in a plane at right angles to the axis of the crank shaft, valves nofmally cl'osing theinn'ei" ends of said dhcts, a duct l'ez'iding from the tippers portion of the'com mon clearance cha1nher, a Valve closing I said last-ment1oned duct, an 1gn1t1on de-.

1. a, w v I I. n. vice seated 1n the all of the common clearan'ce ch'ambe'i" and disposed above the inner end ofth'e (inter one of the two ducts that i enter the l'o'tter portion of the common cl'eai?- a'nce chamber, aca'm' shaft arranged to oper- .,:I=i ate at hall the speed of the crank shaft,

'means actuated by said cam shaft" TEOI succ'essivly open'ingth-e'two Valves that control the ducts communicating fwitli the lo-W'er is =1 r, i 1 ,1 A- 1| portlon oi the common clearance chamber and means operated from saicl cam shaft for unseating the valve that controls the common clearan'cechamhr.

5. In a temstioke cycl-e internal com bustion engine, a combustion cylinder, a piston rranged 1501* o bei ation therein, a

duct leading from the tippe'i p'oftion of said crank shaft to Which said piston is connected, a common compression and combustion cle'ai'anc' chamb'e extending laterally "from the head end of the cham er in the combustion c'ylindeiflfa pair of charge volume inlet di ct's leading to the lowei" par tion of said common clearance chamloer, said duets, being disposed one behind the other and in alignment with the axis of the combustion cylinder, valves normally closing the inner ends of said inlet ducts, a cam shaft lying parallel with the crank shaft and arranged to operate at half the speed thereof and a pair of valve-actuating rocker arms arranged in tandem in a plane at right angles to the plane occupied by the axis of the crank shaft and which rocker arms are actuated by a cam on said cam 10 shaft.

In testimony whereof I have signed my name to this specification. v I

EVERETT R. BURTNETT. 

